<button
  nz-button
  [nzType]="'default'"
  [nzTrigger]="'click'"
  [nzLoading]="loading"
  nz-dropdown
  [nzClickHide]="false"
  [nzDropdownMenu]="columnsDropdown"
  class="columns-toggle"
>
  <span nz-icon [nzType]="'more'" [nzTheme]="'outline'"></span> 显示字段
</button>

<nz-dropdown-menu #columnsDropdown="nzDropdownMenu">
  <ul nz-menu nzSelectable class="menu">
    <li
      *ngFor="let item of service.columns"
      nz-menu-item
      nz-checkbox
      [nzChecked]="item.pinned"
      (nzCheckedChange)="onColumnsToggle($event, item)"
      class="m-0"
    >{{item.name}}</li>
  </ul>
</nz-dropdown-menu>
